What tough exterior layer of the hair has the purpose of surrounding the inner layers and protecting the hair from damage?

Which layer of the hair is located directly beneath the cuticle layer and is responsible for the incredible strength and elasticity of human hair?

Which layer of hair is the innermost layer of the hair, and often called the pith or core of the hair?

The term ph is an abbreviation used for potential ______, and the symbol ph represents the quantity of _________ ions in solution.

The _____ measures the acidity and alkalinity of a substance by measuring the quantity of hydrogen ions it contains.

The range of numbers used in the ph scale is _______

Chemical hair texturizers temporarily raise the ph of the hair to an alkaline state in order to ______.

in the restructuring process, coarse, resistant hair with a strong compact cuticle requires a chemical solution that is ________.

what are the basic building clocks of hair that affect how chemical solutions react?

Which compounds are made up of carbon, oxygen, hydrogen, nitrogen, and sulfur?

Which chemical bonds, also known as end bonds, join amino acids together, end-to-end like beads?

What are long, coliled polypeptide chains linked together end-to-end like beads?

The cortex of the hair is made up of millions of polypeptide chains cross-linked by three types of side bonds

What chemical side bonds are formed when two sulfur-type chains are joined together?

Which bonds are relatively weak physical side bonds resulting from an attraction between negative and positive electrical charges, and are easily broken by changes in ph.

Hydrogen bonds are weak physical side bonds that result from an attraction between negative and positve electrical charges and are easily broken by water or heat, but reform as the hair is _______.

_____ is a two-step process in which the hair first undergoes a physical change caused by water or heat, but reform as the hair is __________.

What determines the size of the curl in a permanent waving process?

In permanent waving, the shape and type of curl are determined by the shape and type of rod and the ________.

Once in the cortex, the waving solution breaks the disulfide bonds through a chemical reaction called _________.

In permanent waving, the reduction reaction is due to the addition of _____.

What are the most common reducing agents used in permanent waving?

The _____ of the permanent waving solution is determined primarily by the concentration of the reducing agent, or thio.

The active ingredient or reducing agent in alkaline permanent waves is _____.

What is the second factor in the overall stength of the waving solution?

Alkaline waves, also known as ______, were developed in 1941.

Most alkaline permanent waves have ph between ______

What is the main active ingredient in true acid and acid-balanced waving lotions?

All acid waves have three components: permanent waving lotion, neutralizer, and ______.

Most acid waves used in salons have a ph value between _____.

Modern acid waves are actually _____ waves, which are permanent waves that have a 7.0 or neutral ph

Exothermic waves create a chemical reaction that heats the waving solution and speeds up ________.

Waves that are activated from an outside heat source, such as a conventional hood-type hair dryer, are _________.

______ waves are perms using an ingredient that does not evaporate as readily as ammonia , so that there is a very little odor associated with their use.

It is important for stylists to remember that ammonia-free does not necessarily mean______.

What waving solutions use an ingredient other than ATG, such as cysteamine or mercaptamine, as the primary reducing agent?

______ waves are permanent solutions based on sulfites, considered very weak, and are usually marketed as body waves or alternative waves.